Dielectric and electrical properties of lead zirconate titanate

www.derpharmachemica.com t Available online a Scholars Research Library Der Pharma Chemica, 2015, 7(10):175-185 (http://derpharmachemica.com/archive.html) ISSN 0975-413X CODEN (USA): PCHHAX 175 www.scholarsresearchlibrary.com Dielectric and electrical properties of lead zirconate titanate R. Balusamy a , P. Kumaravel b and N. G. Renganathan c* a Department of Mechanical Engineering, Al-Ameen Engineering College, Erode b Department of Mechanical Engineering, Institute of Road and Transport Technology, Erode c School of Basic Sciences, Vel Tech University, Chennai _____________________________________________________________________________________________ ABSTRACT Lead zirconate titanate (PZT) (P b Z r O 3 - P b T i O 3 ) were prepared by mixed oxide method at 1100 o C. Crystalline nature of the synthesized PZT has been confirmed by X-ray powder diffraction studies. The particle size and strain is calculated from X-ray peak broadening analysis by using Williamson-Hall plot. The crystallite size is also calculated using Debye-Scherrer’s formula. Also, the surface morphology and particle size of the samples were imaged using scanning electron microscopy (SEM). Dielectric measurement demonstrates that decrease in dielectric constant with increase in temperature. The temperature dependence of the ac conductivity indicated that the conduction process is due to singly ionized (in ferroelectric region) and doubly ionized (in paraelectric region). Key words: PZT ceramics, dielectric spectroscopy, dielectric losses, SEM. _____________________________________________________________________________________________ INTRODUCTION Lead zirconate titanate (PZT) – a ferroelectric ceramic material has piezoelectric properties and reciprocal behavior. This material is used to convert electrical energy into mechanical energy and vice-versa. The material properties of PZT have been the subject for significant research in recent years due to its excellent applications in micro- electromechanical (MEMS) and nano-electromechanical (NEMS) devices. Since it is a potential candidate for sensor applications the material needs further research. Micro and nano sensors are precisely calibrated to work within a set range of specifications. It is a well known ferroelectric material and it has wide application as such as transducers, actuators, sensors and motors. Because of its high density, low hydrostatic piezoelectric coefficients of charge and voltage it is useful for hydrophones and ultrasonic devices. It has been focused on composite fabrication of PZT based piezoelectric materials for sensing and actuating. PZT is also used in the manufacture of ceramic resonators for reference timing in electronic circuitry. Being pyroelectric, this material develops a voltage difference across two of its faces when it experiences a temperature change. As a result, it can be used as a heat sensor. Prior to sol gel processing techniques, PZT films were prepared using more costly and intensive techniques such as RF sputtering, electron beam evaporation, and ion beam deposition [1]. Commercially used PZT ceramics are always modified by different dopants and are divided into the “soft” (donor doped) and “hard” (acceptor doped) groups which are normally prepared by substituting the A-site or B-site ions with donor and acceptor dopants, respectively [2]. Compared with the undoped composition, hard PZT shows lower permittivity, piezoelectric coefficients and elastic compliances, low dielectric and mechanical losses, lowered resistivity, pronounced ageing, and pinched ferroelectric hysteresis in aged state. In contrast, soft PZT shows higher properties, larger losses, improved resistivity, low ageing, square polarization loops, easy poling and depoling [3,4]. Electrical properties of PZT ceramics were

Dielectric and electrical properties of lead zirconate titanate

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